I also "take calls from home". My calls are sent to me by a British Chatline. Usually when I am sent calls the number shows as unavailable, but from time to time this number appears. Maybe you were still logged in and did not realize it?

I got a call from this number and tried to answer it as I work taking calls at home and it was just dead air.  It was 4:16am.  I have no idea what prompted this call, how they got the number or anything, but it's far far too late for telemarketers to legally be calling me.